On Tue, Nov 15, 2016 at 2:13 PM, Norihiro Tanaka <nori...@kcn.ne.jp> wrote: > > On Tue, 15 Nov 2016 11:35:15 -0800 > Jim Meyering <j...@meyering.net> wrote: > >> I suppose you mean in addition to the S_ISFIFO test? That sounds good. >> We should retain the optimization when reading from stdin that is a >> non-pipe. > > This can also happen in stdin. If we redirect stdout to /dev/null, > grep-2.26 exits immediately and prompt is returned. > > - grep-2.25 > > $ grep . >/dev/null > a <<input a and newline > b <<input b and newline > c <<input c and newline > > - grep-2.26 > > $ src/grep . >/dev/null > a <<input a and newline > $
Good point. While I suspect that would be much less likely to cause trouble in practice, I would now rephrase: We should retain the optimization when reading from stdin that is neither a pipe nor a tty.
